The present invention relates to a connector of a fuel pipe for vehicle, and more particularly, to a connector of a fuel pipe for vehicle, in which an insertion hole formed between guide members of a latch are extended or narrowed in a perfect round shape, thereby smoothly mounting and separating a pipe.
In general, a fuel system, which provides an engine with necessary fuel in all operation condition to be easily burned, is an important apparatus which influences a performance, especially output, and economization of the engine. A fuel injection system, which is a principal part of the fuel system, provides the engine with fuel properly.
A fuel feed apparatus comprises a fuel tank for storing fuel, a fuel filter for removing foreign matters from the fuel, a fuel pump for delivering the fuel, and a canister for preventing gasoline vapor from being discharged in the air when the engine is stopped. The components are connected to each other through fuel pipes.
FIG. 1 is a flow chart showing a general flow of fuel. As shown in FIG. 1, a fuel feed pipe 10 connects a fuel pump 16, which forcedly delivers the fuel stored in a fuel tank 12 toward an engine 14, to a fuel injection rail 20 through a fuel filter 18. The fuel feed pipe 10 supplies all injectors (not shown) with equal pressure and amount from the fuel. A fuel recovery pipe 22 returns the remainder of fuel from the fuel injection rail 20 into the fuel tank 12. That is, although the fuel pump 16 delivers a predetermined amount of fuel toward the engine 14, the fuel system remains a small amount of fuel, as maintaining the pressure of about 3 kg/cm3. Therefore, the remainder of fuel is returned into the fuel tank 12 through the fuel recovery pipe 22.
When the engine is stopped, evaporative fuel gas to be vaporized in the fuel tank 12 is collected and stored into a canister 24. The canister 24 is connected to the engine 14 and the fuel tank 12 through evaporative fuel gas connecting pipes 26. The diameter of the pipe is about 8 to 10 mm. Connectors 28 are disposed on joint portions of the pipes. As the connectors 28 are required on joint portions of the steel pipes and plastic pipes.
However, the conventional steel tube made of metal is very heavy and can be corroded. The rubber tube is light, but must be coated with fluoride film not to be melted with gasoline, thereby causing a rise of manufacturing cost. Furthermore, because a large volume of hydrocarbon existing in gasoline goes through the inner wall of the rubber tube and is discharged in the air, thereby causing environmental pollution.
To solve the above problems, various kinds of tubes which are made of special plastics in place of steel or rubber are proposed, and recently, technique related to the connector for easily connecting and separating the plastic tube is being lively developed.
Meanwhile, a connector made of plastic tube for connecting fuel pipes of vehicle is disclosed in U.S. Pat. No. 5,374,088. As shown in FIGS. 2 and 3, a latch 30 is inserted into a side of a connector housing (not shown) and fixed jaws 32 are formed on the latch 30 for latching a bead 42 formed on the peripheral surface of a pipe 40. Push members 34 are elastically connected to the opposite sides of the fixed jaws 32 by resilient members 36 to elastically extend and narrow a space between the fixed jaws 32.
In the conventional connector of the fuel pipe, when the pipe 40 is inserted into the space between the fixed jaws 32 of the latch 30 and the bead 42 of the pipe 40 is contacted to the fixed jaws 32, the space between the fixed jaws 32 is extended over a powerful elastic force of the resilient members 36. At this time, the pipe 40 is inserted into the connector housing as well as the bead 42 of the pipe 40 is caught to the inner portion of the fixed jaws 32 of the latch 30, so that the pipe 40 is fastened to the connector housing.
However, the elastic force of the resilient members 36 are weak, thereby the pipe 40 is easily separated from a little external power.
To separate the pipe 40 from the space between the fixed jaws 32 of the latch 30, when the fixed jaws 32 are extended outward after pressing the push members 34 formed on the opposite sides of the latch 30, the pipe 40 .is separated from the connector.
When the push members 34 of the latch 30 are pressed, the fixed jaws 32 connected to the resilient members 36 are extended outward, thereby separating the pipe 40 from the space between the fixed jaws 32. However, the fixed jaws 32 are extended not in a perfect round but in a distorted round, thereby the bead 42 of the pipe 40 is not smoothly separated from the fixed jaws 32. That is, when the push members 34 are pressed, the pressure must be evenly transferred to the fixed jaws 32 through the medium of the resilient members 36 to maintain its round shape. However, the conventional fixed jaws 32 are distorted when extending, thereby the bead 42 is caught to a portion of the fixed jaws 32 when the pipe 40 is separated from the connector.
It is, therefore, an object of the present invention to provide a connector of a fuel pipe for vehicle, which allows a pipe to be simply mounted and detached by adjusting a latch.
To accomplish the above object, the present invention provides a connector of a fuel pipe for vehicle, comprising a connector housing installed to a fuel feed pipe, a fuel recovery pipe and an evaporative fuel gas connecting pipe and a latch connected into the connector housing, wherein the latch includes: guide members oppositely located at a prescribed interval, each guide member having a curved inner surface, a slant surface on a front portion thereof for guiding an insertion of the pipe, a fixed jaw on a rear portion thereof for retaining a bead formed on the peripheral surface of the pipe, and a guide groove formed in the center portion thereof; push members vertically located away from the opposite sides of the guide members; and two pair waved resilient members elastically disposed on the upper and lower portions of the guide members, the two pair waved resilient members connecting the push members and the guide members to provide a powerful elastic force to the rear portion of the two pair waved resilient members, so that the guide members are extended outward when the push members are pressed. The guide grooves are combined with a guide rail formed inside the connector housing, thereby extending the guide members in a perfect round shape.